Motorhead frontman Lemmy has died aged 70, two days after learning he had cancer, the British band has announced.
Lemmy formed the rock group in 1975 and recorded 22 albums, including Ace of Spades, as he became one of music's most recognisable voices and faces.
The band said on its Facebook page: "Our mighty, noble friend Lemmy has passed away after a short battle with an extremely aggressive cancer."
Lemmy was born Ian Fraser Kilmister in Burslem, Stoke-on-Trent, in 1945.
He lived in Anglesey, Wales, as a child and acquired the nickname Lemmy while at school, although he claimed to have had no idea where it came from.
As Lemmy of Motorhead, he became known for his fast and furious bass guitar playing and gravelly voice.
The band added: "We cannot begin to express our shock and sadness, there aren't words."
They urged fans to play Lemmy's music loud and "have a drink or few", saying: "Celebrate the life this lovely, wonderful man celebrated so vibrantly himself.
"He would want exactly that."
Lemmy, who was the only constant member of Motorhead, lived in Los Angeles and died at home with his family on Monday.
He had been diagnosed with cancer on Saturday - two days after his 70th birthday.
Heavy metal star Ozzy Osbourne was among those to pay tribute on social media.
'Warrior and legend'
He tweeted: "Lost one of my best friends, Lemmy, today. He will be sadly missed. He was a warrior and a legend.
"I will see you on the other side."
Queen's Brian May described Lemmy as "our utterly unique friend".
Metallica tweeted: "Lemmy, you are one of the primary reasons this band exists. We're forever grateful for all of your inspiration.''
Kiss star Gene Simmons said: "Lemmy: Rest In Peace. Shake the heavens, my friend."
Guns N' Roses bassist Duff McKagan added: "Rest In Peace Lemmy. A hell of a man who suffered no fools.
"U shall be missed brother, and, THANK u 4 the years of unwavering kick ass R&R."
And Rage Against the Machine's Tom Morello described Lemmy as "a true rock icon".
His death comes just weeks after former Motorhead drummer Phil Taylor died at the age of 61.
Ex-Motorhead guitarist "Fast" Eddie Clarke, who played with the group between 1976 and 1982, said on Facebook: "I am devastated. We did so much together, the three of us.
"The world seems a really empty place right now. I am having trouble finding the words ... He will live on in our hearts. R.I.P Lemmy!"
Lemmy was credited with introducing punk sounds into the heavy metal genre - and having a wild offstage reputation.
He first became involved in the Manchester music scene, before going to London.
There he had a stint as a roadie with Jimi Hendrix and briefly played in progressive rock band Opal Butterfly.
In 1972 he joined space-rock band Hawkwind on bass but left after being busted for drug possession on a tour of Canada in 1975.
Lemmy went on to form Motorhead - the name is US slang for someone who takes speed - and recorded 22 studio albums with the band between 1977 and 2015.
The band achieved critical acclaim with the 1980 Ace of Spades album, which reached number four in the UK chart.
They recently released Bad Magic and were set to play dates in the UK and Europe over the next few months as part of a world tour.
John Robb, a musician and editor of the Louder Than War website, told the BBC: "Lemmy's voice and the sound of the bass guitar was exactly the same.
"It was a fantastic bluff gruffness which is so attractive, so hypnotic.
"It's a really great sound... It's a mistake to say it's just a noise because he wrote really good songs."